JPH06102250A - Liquid chromatograph direct connection type mass spectroscope - Google Patents

Abstract

PURPOSE:To enable an observer to accomplish a measurement utterly ignoring a timing of outputting a switching signal by processing a signal of a detector by a data processing of data of a mass spectrometer to output a switching signal to a switching valve. CONSTITUTION:A liquid chromatograph direct connection type mass spectrometer is made up of a liquid chromatography device which is composed of a pump 2, a separation column 4 and a detector 5, a switching valve 9 to introduce a specified sample selectively into a mass spectrometer, a mass spectrometer 11 which performs a mass scattering, a detector 5 and a data processor 12 which processes a signal from the mass spectrometer 11 while controlling the switching valve 9 and the mass spectrograph 11 simultaneously.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus in which a liquid chromatograph and a mass spectrometer are combined with each other, and a signal processing apparatus of the mass spectrometer is made to judge a signal from a detector to control a switching valve. , For automation and reliable operation.

[0002]

2. Description of the Related Art At present, a liquid chromatograph direct coupling type mass spectrometer apparatus has been developed as an apparatus capable of continuously performing compound separation to identification, and is used for pharmaceuticals, agricultural chemicals, food additives, industrial materials, other natural products and synthetic products. It is widely used and widely used in the production and research of goods.

However, liquid chromatographs often deal with complicated samples in which a large number of components are mixed, and when introduced into the ion source of a mass spectrometer, contamination of the ion source is caused in these samples, making continuous measurement impossible. There are many things that make it possible. As a measure against this problem, as shown in Japanese Patent Laid-Open No. 1-140060, a sample that is connected to a switching valve between the liquid chromatograph and the mass spectrometer and leads to contamination of the ion source is currently being used. Is eliminated without being introduced into the interface of the mass spectrometer, and only when the target sample passes through the detector, the switching valve is switched to introduce into the interface of the mass spectrometer. In this case, the switching valve is manually switched by the measurer while confirming that the target peak has eluted while looking at the detector. Alternatively, a timer is set, the time when the target peak elutes is confirmed in advance, and the switching valve is set to switch to that time. Another method is to provide a voltage comparison circuit at the output terminal of the detector so that the valve automatically switches above the set reference voltage.

[0004]

In the above three types of methods, there are some problems when an operator who is not familiar with the liquid chromatograph apparatus uses this system to continuously measure similar samples one after another. . In the first case, there is the inconvenience that the measurer has to stay with the device until the peak appears. In the second case, the valve 9 is automatically switched, but when a plurality of peaks are selected and introduced into the mass spectrometer 11, it is necessary to program all valve switching times in advance, and when there are many components. ,
It becomes a troublesome work. Moreover, when the measurement is repeated, there is a possibility that the target total amount of the sample cannot be properly introduced into the mass spectrometer 11 because the timing of switching the valve 9 is not correct due to a slight shift in the time of peak appearance. 3 more
In the second case, the valve 9 is automatically switched and there is no problem with the timing, but the switching timing is determined only by the peak detection signal, so if the peak signal to be excluded is equal to the target peak, be sure There is a possibility that switching of the valve 9 will not occur. In the present invention, when repeatedly measuring a sample of the same component, the liquid chromatogram is measured once before being introduced into the mass spectrometer 11 and the liquid chromatogram is taken in, and the operator aims based on the data. Specify the peak in advance. In the subsequent measurement, the control of the switching valve 9 is controlled from the data processing device 12 of the mass spectrometer 11 on the basis of the peak designation, so as to be automated and to improve efficiency and reliability.

[0005]

An object of the present invention is to detect a sample separated by a liquid chromatograph with a detector 5 connected thereafter, and send the signal to a data processor 12 of a mass spectrometer 11 to display a screen. By displaying the data, and the measurer specifying the target peak based on the data, a signal is output from the data processing device 12 of the mass spectrometer 11 to the electric switching valve 9 in the case of subsequent repeated measurements. It is achieved by automatically controlling.

[0006]

The signal sent from the detector 5 is processed by the data processing device 12 of the mass spectrometer 11 to perform peak judgment. If the measurer specifies the number of the peak to be introduced into the mass spectrometer 11, a signal is output to the electric switching valve 9 at the time when the target peak is detected. It can be incorporated into a total of 11.
Moreover, the measurer does not need to be on the device during the measurement.

[0007]

Embodiments of the present invention will be described with reference to FIGS. FIG. 1 shows the configuration of the entire apparatus. The mixed sample is injected from the injector 3 and is carried to the separation column 4 by the mobile phase solvent sent from the solvent tank 1 by the solution sending pump 2. The sample separated into each component in the separation column 4 is detected by the detector 5, and a signal is sent to the data processing device 12 of the mass spectrometer 11 to be displayed as a liquid chromatogram. Now A,
Consider a case where five peaks of B, C, D, and E are detected (see FIG. 3), and of these, only B and D are introduced into the mass spectrometer 11. In the peak determination, a threshold value is set for the signal intensity from the detector 5, and a peak value exceeding the threshold value is determined as a peak. The threshold can be changed to any value by the measurer (see FIG. 4). Before the measurement to be introduced into the mass spectrometer 11, the measurer switches the switching valve 9 so that the sample is not introduced into the mass spectrometer 11, performs the measurement by the liquid chromatograph, and performs the data processing of the mass spectrometer 11. check the peak on the screen of the device 12, have specified or introducing any peak in advance in the mass spectrometer 11. When the peak is determined, a number is assigned in the order of retention time, and the measurer may specify the number. After designating the peaks of B and D, actual measurement is performed. In the initial state, the switching valve 9 is in the state 1 shown in FIG.
Only the same mobile phase solvent as in the solvent tank 1 contained in the solvent tank 6 is sent to the interface 10 of No. 1 by the liquid sending pump 7. Data processing device 1 of mass spectrometer 11
2 outputs a switching signal to the switching valve 9 at the same time that the rising signal of the peak B is sent from the detector 5 (see FIG. 3), and the state of the switching valve changes to the state 2 of FIG. (See FIG. 2), the peak B passing through the detector 5 is the interface 1 of the mass spectrometer 11.
Sent to 0 and ionized. The data processing device 12 of the mass spectrometer 11 outputs the switching signal to the switching valve 9 again when the peak B has been eluted, and the switching valve 9 returns to the state 1. The switching signal output timing is determined by the signal strength threshold value and the retention time (see FIG. 5). The peak retention time T is set to have a width of a certain time t, and the switching signal is changed at a time point a when the threshold value is exceeded within a range from T−t to T + t and a time point a ′ when the threshold value is less than or equal to the threshold value. Is output. Further, the threshold and the width t of the fixed time can be changed to arbitrary values. By repeating the same operation when the peak D is detected, the peaks A, C, and E are sent out to the waste liquid tank 13 as they are after passing through the detector 5, and only the peaks B and D are reliably mass spectrometer ion source. Will be introduced to.

[0008]

The detector signal is processed by the data processing device of the mass spectrometer and the switching signal for the switching valve is output, so that the operator can specify the peak once and then switch. The measurement can be performed without paying attention to the timing of outputting the signal. Further, when the peak is designated, the liquid chromatogram is displayed on the screen of the data processing device, so that the setting can be easily performed.

[Brief description of drawings]

FIG. 1 is a diagram showing an entire apparatus configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a state of an electric switching valve.

FIG. 3 is a diagram showing an example of a peak detected by a detector, an example of an output signal to the switching valve, and a state of the switching valve.

FIG. 4 is a diagram showing a peak determination method.

FIG. 5 is a diagram showing a timing of outputting a switching signal to an electric switching valve.

[Explanation of symbols]

1 ... Mobile phase solvent tank, 2 ... Liquid feed pump, 3 ... Injector, 4 ...
Separation column, 5 ... Detector, 6 ... Mobile phase solvent tank (same as 1), 7 ... Liquid feed pump, 8 ... Flow path piping, 9 ... Electric switching valve, 10 ... Mass spectrometer interface, 11 ... Mass Analyzer, 12 ... Data processing device of mass spectrometer, 13 ... Waste solvent tank.

Claims (1)

[Claims] 1. A liquid chromatograph comprising a mobile phase solvent tank for separating a mixed sample in a solution, a liquid feed pump, a sample injection device, and a separation column, a detector for detecting the separated components, and a detection. A switching valve that can switch whether to directly introduce the effluent from the analyzer to the interface as it is, an interface to introduce the effluent from the switching valve to the ion source of the mass spectrometer, and ionize the introduced sample. Directly connected to a liquid chromatograph consisting of an ion source and a mass spectrometer that performs mass dispersion, a detector, and a data processing device that processes signals from the mass spectrometer and at the same time controls the switching valve and the mass spectrometer. -Type mass spectrometer device, the signal from the detector regarding the separated and eluted sample is sent to the data processing device of the mass spectrometer. In addition to displaying it on the screen of the data processing device, the peak judgment is performed with the peak showing the signal strength exceeding the preset threshold value, and the peak value is specified by the measurer from the result. Based on the designation, the peak retention time and the threshold value of the signal intensity from the detector are set to output a control signal to the switching valve so that only the target sample is introduced into the mass spectrometer. Liquid chromatograph direct connection type mass spectrometer device characterized by: